Remark. This is an accessible companion piece to our deep-dive research post and lecture. For the full technical breakdown, check out the research post and watch the lecture.

With the recent publication of Google Quantum AI’s paper on quantum computing, discussions around the timeline for a Cryptographically Relevant Quantum Computer (CRQC) have intensified. While opinions on the timeline vary, the consensus in the cryptography community is clear: we need to start preparing and surveying quantum-secure algorithms now.

The first major task is to choose a post-quantum-secure digital signature scheme to replace the quantum-vulnerable elliptic curve cryptography we use today in Bitcoin. But upgrading from Schnorr and ECDSA isn't as simple as swapping out one algorithm for another. The community is currently tackling two massive questions: how we safely execute this transition, and which post-quantum (PQ) scheme we actually transition to. This post focuses entirely on the “which” part, breaking down one of the most promising PQ signature families.

Here is a look at the current post-quantum landscape, why Blockstream is heavily researching "lattice-based" cryptography, and how these signatures actually function.

...read more at blockstream.com